ref: e65f5987f6eea95bfbb0876cc0a966d1d82f5841
dir: /vp8/encoder/firstpass.c/
/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "math.h"
#include "limits.h"
#include "block.h"
#include "onyx_int.h"
#include "variance.h"
#include "encodeintra.h"
#include "vp8/common/setupintrarecon.h"
#include "mcomp.h"
#include "firstpass.h"
#include "vpx_scale/vpxscale.h"
#include "encodemb.h"
#include "vp8/common/extend.h"
#include "vp8/common/systemdependent.h"
#include "vpx_scale/yv12extend.h"
#include "vpx_mem/vpx_mem.h"
#include "vp8/common/swapyv12buffer.h"
#include <stdio.h>
#include "rdopt.h"
#include "ratectrl.h"
#include "vp8/common/quant_common.h"
#include "encodemv.h"
//#define OUTPUT_FPF 1
#if CONFIG_RUNTIME_CPU_DETECT
#define IF_RTCD(x) (x)
#else
#define IF_RTCD(x) NULL
#endif
#if CONFIG_HIGH_PRECISION_MV
#define XMVCOST (x->e_mbd.allow_high_precision_mv?x->mvcost_hp:x->mvcost)
#else
#define XMVCOST (x->mvcost)
#endif
extern void vp8_build_block_offsets(MACROBLOCK *x);
extern void vp8_setup_block_ptrs(MACROBLOCK *x);
extern void vp8cx_frame_init_quantizer(VP8_COMP *cpi);
extern void vp8_set_mbmode_and_mvs(MACROBLOCK *x, MB_PREDICTION_MODE mb, int_mv *mv);
extern void vp8_alloc_compressor_data(VP8_COMP *cpi);
#define IIFACTOR 12.5
#define IIKFACTOR1 12.5
#define IIKFACTOR2 15.0
#define RMAX 128.0
#define GF_RMAX 96.0
#define ERR_DIVISOR 150.0
#define KF_MB_INTRA_MIN 300
#define GF_MB_INTRA_MIN 200
#define DOUBLE_DIVIDE_CHECK(X) ((X)<0?(X)-.000001:(X)+.000001)
#define POW1 (double)cpi->oxcf.two_pass_vbrbias/100.0
#define POW2 (double)cpi->oxcf.two_pass_vbrbias/100.0
static void find_next_key_frame(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame);
static int select_cq_level( int qindex )
{
int ret_val = QINDEX_RANGE - 1;
int i;
double target_q = ( vp8_convert_qindex_to_q( qindex ) * 0.5847 ) + 1.0;
for ( i = 0; i < QINDEX_RANGE; i++ )
{
if ( target_q <= vp8_convert_qindex_to_q( i ) )
{
ret_val = i;
break;
}
}
return ret_val;
}
// Resets the first pass file to the given position using a relative seek from the current position
static void reset_fpf_position(VP8_COMP *cpi, FIRSTPASS_STATS *Position)
{
cpi->twopass.stats_in = Position;
}
static int lookup_next_frame_stats(VP8_COMP *cpi, FIRSTPASS_STATS *next_frame)
{
if (cpi->twopass.stats_in >= cpi->twopass.stats_in_end)
return EOF;
*next_frame = *cpi->twopass.stats_in;
return 1;
}
// Read frame stats at an offset from the current position
static int read_frame_stats( VP8_COMP *cpi,
FIRSTPASS_STATS *frame_stats,
int offset )
{
FIRSTPASS_STATS * fps_ptr = cpi->twopass.stats_in;
// Check legality of offset
if ( offset >= 0 )
{
if ( &fps_ptr[offset] >= cpi->twopass.stats_in_end )
return EOF;
}
else if ( offset < 0 )
{
if ( &fps_ptr[offset] < cpi->twopass.stats_in_start )
return EOF;
}
*frame_stats = fps_ptr[offset];
return 1;
}
static int input_stats(VP8_COMP *cpi, FIRSTPASS_STATS *fps)
{
if (cpi->twopass.stats_in >= cpi->twopass.stats_in_end)
return EOF;
*fps = *cpi->twopass.stats_in;
cpi->twopass.stats_in =
(void*)((char *)cpi->twopass.stats_in + sizeof(FIRSTPASS_STATS));
return 1;
}
static void output_stats(const VP8_COMP *cpi,
struct vpx_codec_pkt_list *pktlist,
FIRSTPASS_STATS *stats)
{
struct vpx_codec_cx_pkt pkt;
pkt.kind = VPX_CODEC_STATS_PKT;
pkt.data.twopass_stats.buf = stats;
pkt.data.twopass_stats.sz = sizeof(FIRSTPASS_STATS);
vpx_codec_pkt_list_add(pktlist, &pkt);
// TEMP debug code
#if OUTPUT_FPF
{
FILE *fpfile;
fpfile = fopen("firstpass.stt", "a");
fprintf(fpfile, "%12.0f %12.0f %12.0f %12.0f %12.0f %12.4f %12.4f"
"%12.4f %12.4f %12.4f %12.4f %12.4f %12.4f %12.4f"
"%12.0f %12.0f %12.4f %12.0f %12.0f %12.4f\n",
stats->frame,
stats->intra_error,
stats->coded_error,
stats->sr_coded_error,
stats->ssim_weighted_pred_err,
stats->pcnt_inter,
stats->pcnt_motion,
stats->pcnt_second_ref,
stats->pcnt_neutral,
stats->MVr,
stats->mvr_abs,
stats->MVc,
stats->mvc_abs,
stats->MVrv,
stats->MVcv,
stats->mv_in_out_count,
stats->new_mv_count,
stats->count,
stats->duration);
fclose(fpfile);
}
#endif
}
static void zero_stats(FIRSTPASS_STATS *section)
{
section->frame = 0.0;
section->intra_error = 0.0;
section->coded_error = 0.0;
section->sr_coded_error = 0.0;
section->ssim_weighted_pred_err = 0.0;
section->pcnt_inter = 0.0;
section->pcnt_motion = 0.0;
section->pcnt_second_ref = 0.0;
section->pcnt_neutral = 0.0;
section->MVr = 0.0;
section->mvr_abs = 0.0;
section->MVc = 0.0;
section->mvc_abs = 0.0;
section->MVrv = 0.0;
section->MVcv = 0.0;
section->mv_in_out_count = 0.0;
section->new_mv_count = 0.0;
section->count = 0.0;
section->duration = 1.0;
}
static void accumulate_stats(FIRSTPASS_STATS *section, FIRSTPASS_STATS *frame)
{
section->frame += frame->frame;
section->intra_error += frame->intra_error;
section->coded_error += frame->coded_error;
section->sr_coded_error += frame->sr_coded_error;
section->ssim_weighted_pred_err += frame->ssim_weighted_pred_err;
section->pcnt_inter += frame->pcnt_inter;
section->pcnt_motion += frame->pcnt_motion;
section->pcnt_second_ref += frame->pcnt_second_ref;
section->pcnt_neutral += frame->pcnt_neutral;
section->MVr += frame->MVr;
section->mvr_abs += frame->mvr_abs;
section->MVc += frame->MVc;
section->mvc_abs += frame->mvc_abs;
section->MVrv += frame->MVrv;
section->MVcv += frame->MVcv;
section->mv_in_out_count += frame->mv_in_out_count;
section->new_mv_count += frame->new_mv_count;
section->count += frame->count;
section->duration += frame->duration;
}
static void subtract_stats(FIRSTPASS_STATS *section, FIRSTPASS_STATS *frame)
{
section->frame -= frame->frame;
section->intra_error -= frame->intra_error;
section->coded_error -= frame->coded_error;
section->sr_coded_error -= frame->sr_coded_error;
section->ssim_weighted_pred_err -= frame->ssim_weighted_pred_err;
section->pcnt_inter -= frame->pcnt_inter;
section->pcnt_motion -= frame->pcnt_motion;
section->pcnt_second_ref -= frame->pcnt_second_ref;
section->pcnt_neutral -= frame->pcnt_neutral;
section->MVr -= frame->MVr;
section->mvr_abs -= frame->mvr_abs;
section->MVc -= frame->MVc;
section->mvc_abs -= frame->mvc_abs;
section->MVrv -= frame->MVrv;
section->MVcv -= frame->MVcv;
section->mv_in_out_count -= frame->mv_in_out_count;
section->new_mv_count -= frame->new_mv_count;
section->count -= frame->count;
section->duration -= frame->duration;
}
static void avg_stats(FIRSTPASS_STATS *section)
{
if (section->count < 1.0)
return;
section->intra_error /= section->count;
section->coded_error /= section->count;
section->sr_coded_error /= section->count;
section->ssim_weighted_pred_err /= section->count;
section->pcnt_inter /= section->count;
section->pcnt_second_ref /= section->count;
section->pcnt_neutral /= section->count;
section->pcnt_motion /= section->count;
section->MVr /= section->count;
section->mvr_abs /= section->count;
section->MVc /= section->count;
section->mvc_abs /= section->count;
section->MVrv /= section->count;
section->MVcv /= section->count;
section->mv_in_out_count /= section->count;
section->duration /= section->count;
}
// Calculate a modified Error used in distributing bits between easier and harder frames
static double calculate_modified_err(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame)
{
double av_err = ( cpi->twopass.total_stats->ssim_weighted_pred_err /
cpi->twopass.total_stats->count );
double this_err = this_frame->ssim_weighted_pred_err;
double modified_err;
if (this_err > av_err)
modified_err = av_err * pow((this_err / DOUBLE_DIVIDE_CHECK(av_err)), POW1);
else
modified_err = av_err * pow((this_err / DOUBLE_DIVIDE_CHECK(av_err)), POW2);
return modified_err;
}
static const double weight_table[256] = {
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.031250, 0.062500, 0.093750, 0.125000, 0.156250, 0.187500, 0.218750,
0.250000, 0.281250, 0.312500, 0.343750, 0.375000, 0.406250, 0.437500, 0.468750,
0.500000, 0.531250, 0.562500, 0.593750, 0.625000, 0.656250, 0.687500, 0.718750,
0.750000, 0.781250, 0.812500, 0.843750, 0.875000, 0.906250, 0.937500, 0.968750,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000
};
static double simple_weight(YV12_BUFFER_CONFIG *source)
{
int i, j;
unsigned char *src = source->y_buffer;
double sum_weights = 0.0;
// Loop throught the Y plane raw examining levels and creating a weight for the image
i = source->y_height;
do
{
j = source->y_width;
do
{
sum_weights += weight_table[ *src];
src++;
}while(--j);
src -= source->y_width;
src += source->y_stride;
}while(--i);
sum_weights /= (source->y_height * source->y_width);
return sum_weights;
}
// This function returns the current per frame maximum bitrate target
static int frame_max_bits(VP8_COMP *cpi)
{
// Max allocation for a single frame based on the max section guidelines passed in and how many bits are left
int max_bits;
// For VBR base this on the bits and frames left plus the two_pass_vbrmax_section rate passed in by the user
max_bits = (int)(((double)cpi->twopass.bits_left / (cpi->twopass.total_stats->count - (double)cpi->common.current_video_frame)) * ((double)cpi->oxcf.two_pass_vbrmax_section / 100.0));
// Trap case where we are out of bits
if (max_bits < 0)
max_bits = 0;
return max_bits;
}
void vp8_init_first_pass(VP8_COMP *cpi)
{
zero_stats(cpi->twopass.total_stats);
}
void vp8_end_first_pass(VP8_COMP *cpi)
{
output_stats(cpi, cpi->output_pkt_list, cpi->twopass.total_stats);
}
static void zz_motion_search( VP8_COMP *cpi, MACROBLOCK * x, YV12_BUFFER_CONFIG * recon_buffer, int * best_motion_err, int recon_yoffset )
{
MACROBLOCKD * const xd = & x->e_mbd;
BLOCK *b = &x->block[0];
BLOCKD *d = &x->e_mbd.block[0];
unsigned char *src_ptr = (*(b->base_src) + b->src);
int src_stride = b->src_stride;
unsigned char *ref_ptr;
int ref_stride=d->pre_stride;
// Set up pointers for this macro block recon buffer
xd->pre.y_buffer = recon_buffer->y_buffer + recon_yoffset;
ref_ptr = (unsigned char *)(*(d->base_pre) + d->pre );
VARIANCE_INVOKE(IF_RTCD(&cpi->rtcd.variance), mse16x16) ( src_ptr, src_stride, ref_ptr, ref_stride, (unsigned int *)(best_motion_err));
}
static void first_pass_motion_search(VP8_COMP *cpi, MACROBLOCK *x,
int_mv *ref_mv, MV *best_mv,
YV12_BUFFER_CONFIG *recon_buffer,
int *best_motion_err, int recon_yoffset )
{
MACROBLOCKD *const xd = & x->e_mbd;
BLOCK *b = &x->block[0];
BLOCKD *d = &x->e_mbd.block[0];
int num00;
int_mv tmp_mv;
int_mv ref_mv_full;
int tmp_err;
int step_param = 3;
int further_steps = (MAX_MVSEARCH_STEPS - 1) - step_param;
int n;
vp8_variance_fn_ptr_t v_fn_ptr = cpi->fn_ptr[BLOCK_16X16];
int new_mv_mode_penalty = 256;
// override the default variance function to use MSE
v_fn_ptr.vf = VARIANCE_INVOKE(IF_RTCD(&cpi->rtcd.variance), mse16x16);
// Set up pointers for this macro block recon buffer
xd->pre.y_buffer = recon_buffer->y_buffer + recon_yoffset;
// Initial step/diamond search centred on best mv
tmp_mv.as_int = 0;
ref_mv_full.as_mv.col = ref_mv->as_mv.col>>3;
ref_mv_full.as_mv.row = ref_mv->as_mv.row>>3;
tmp_err = cpi->diamond_search_sad(x, b, d, &ref_mv_full, &tmp_mv, step_param,
x->sadperbit16, &num00, &v_fn_ptr,
XMVCOST, ref_mv);
if ( tmp_err < INT_MAX-new_mv_mode_penalty )
tmp_err += new_mv_mode_penalty;
if (tmp_err < *best_motion_err)
{
*best_motion_err = tmp_err;
best_mv->row = tmp_mv.as_mv.row;
best_mv->col = tmp_mv.as_mv.col;
}
// Further step/diamond searches as necessary
n = num00;
num00 = 0;
while (n < further_steps)
{
n++;
if (num00)
num00--;
else
{
tmp_err = cpi->diamond_search_sad(x, b, d, &ref_mv_full, &tmp_mv,
step_param + n, x->sadperbit16,
&num00, &v_fn_ptr,
XMVCOST, ref_mv);
if ( tmp_err < INT_MAX-new_mv_mode_penalty )
tmp_err += new_mv_mode_penalty;
if (tmp_err < *best_motion_err)
{
*best_motion_err = tmp_err;
best_mv->row = tmp_mv.as_mv.row;
best_mv->col = tmp_mv.as_mv.col;
}
}
}
}
void vp8_first_pass(VP8_COMP *cpi)
{
int mb_row, mb_col;
MACROBLOCK *const x = & cpi->mb;
VP8_COMMON *const cm = & cpi->common;
MACROBLOCKD *const xd = & x->e_mbd;
int recon_yoffset, recon_uvoffset;
YV12_BUFFER_CONFIG *lst_yv12 = &cm->yv12_fb[cm->lst_fb_idx];
YV12_BUFFER_CONFIG *new_yv12 = &cm->yv12_fb[cm->new_fb_idx];
YV12_BUFFER_CONFIG *gld_yv12 = &cm->yv12_fb[cm->gld_fb_idx];
int recon_y_stride = lst_yv12->y_stride;
int recon_uv_stride = lst_yv12->uv_stride;
int64_t intra_error = 0;
int64_t coded_error = 0;
int64_t sr_coded_error = 0;
int sum_mvr = 0, sum_mvc = 0;
int sum_mvr_abs = 0, sum_mvc_abs = 0;
int sum_mvrs = 0, sum_mvcs = 0;
int mvcount = 0;
int intercount = 0;
int second_ref_count = 0;
int intrapenalty = 256;
int neutral_count = 0;
int new_mv_count = 0;
int sum_in_vectors = 0;
uint32_t lastmv_as_int = 0;
int_mv zero_ref_mv;
zero_ref_mv.as_int = 0;
vp8_clear_system_state(); //__asm emms;
x->src = * cpi->Source;
xd->pre = *lst_yv12;
xd->dst = *new_yv12;
x->partition_info = x->pi;
xd->mode_info_context = cm->mi;
vp8_build_block_offsets(x);
vp8_setup_block_dptrs(&x->e_mbd);
vp8_setup_block_ptrs(x);
// set up frame new frame for intra coded blocks
vp8_setup_intra_recon(new_yv12);
vp8cx_frame_init_quantizer(cpi);
// Initialise the MV cost table to the defaults
//if( cm->current_video_frame == 0)
//if ( 0 )
{
int flag[2] = {1, 1};
vp8_initialize_rd_consts(cpi, cm->base_qindex + cm->y1dc_delta_q);
vpx_memcpy(cm->fc.mvc, vp8_default_mv_context, sizeof(vp8_default_mv_context));
vp8_build_component_cost_table(cpi->mb.mvcost, (const MV_CONTEXT *) cm->fc.mvc, flag);
#if CONFIG_HIGH_PRECISION_MV
vpx_memcpy(cm->fc.mvc_hp, vp8_default_mv_context_hp, sizeof(vp8_default_mv_context_hp));
vp8_build_component_cost_table_hp(cpi->mb.mvcost_hp, (const MV_CONTEXT_HP *) cm->fc.mvc_hp, flag);
#endif
}
// for each macroblock row in image
for (mb_row = 0; mb_row < cm->mb_rows; mb_row++)
{
int_mv best_ref_mv;
best_ref_mv.as_int = 0;
// reset above block coeffs
xd->up_available = (mb_row != 0);
recon_yoffset = (mb_row * recon_y_stride * 16);
recon_uvoffset = (mb_row * recon_uv_stride * 8);
// Set up limit values for motion vectors to prevent them extending outside the UMV borders
x->mv_row_min = -((mb_row * 16) + (VP8BORDERINPIXELS - 16));
x->mv_row_max = ((cm->mb_rows - 1 - mb_row) * 16) + (VP8BORDERINPIXELS - 16);
// for each macroblock col in image
for (mb_col = 0; mb_col < cm->mb_cols; mb_col++)
{
int this_error;
int gf_motion_error = INT_MAX;
int use_dc_pred = (mb_col || mb_row) && (!mb_col || !mb_row);
xd->dst.y_buffer = new_yv12->y_buffer + recon_yoffset;
xd->dst.u_buffer = new_yv12->u_buffer + recon_uvoffset;
xd->dst.v_buffer = new_yv12->v_buffer + recon_uvoffset;
xd->left_available = (mb_col != 0);
//Copy current mb to a buffer
RECON_INVOKE(&xd->rtcd->recon, copy16x16)(x->src.y_buffer, x->src.y_stride, x->thismb, 16);
// do intra 16x16 prediction
this_error = vp8_encode_intra(cpi, x, use_dc_pred);
// "intrapenalty" below deals with situations where the intra and inter error scores are very low (eg a plain black frame)
// We do not have special cases in first pass for 0,0 and nearest etc so all inter modes carry an overhead cost estimate fot the mv.
// When the error score is very low this causes us to pick all or lots of INTRA modes and throw lots of key frames.
// This penalty adds a cost matching that of a 0,0 mv to the intra case.
this_error += intrapenalty;
// Cumulative intra error total
intra_error += (int64_t)this_error;
// Set up limit values for motion vectors to prevent them extending outside the UMV borders
x->mv_col_min = -((mb_col * 16) + (VP8BORDERINPIXELS - 16));
x->mv_col_max = ((cm->mb_cols - 1 - mb_col) * 16) + (VP8BORDERINPIXELS - 16);
// Other than for the first frame do a motion search
if (cm->current_video_frame > 0)
{
int tmp_err;
int motion_error = INT_MAX;
int_mv mv, tmp_mv;
// Simple 0,0 motion with no mv overhead
zz_motion_search( cpi, x, lst_yv12, &motion_error, recon_yoffset );
mv.as_int = tmp_mv.as_int = 0;
// Test last reference frame using the previous best mv as the
// starting point (best reference) for the search
first_pass_motion_search(cpi, x, &best_ref_mv,
&mv.as_mv, lst_yv12,
&motion_error, recon_yoffset);
// If the current best reference mv is not centred on 0,0 then do a 0,0 based search as well
if (best_ref_mv.as_int)
{
tmp_err = INT_MAX;
first_pass_motion_search(cpi, x, &zero_ref_mv, &tmp_mv.as_mv,
lst_yv12, &tmp_err, recon_yoffset);
if ( tmp_err < motion_error )
{
motion_error = tmp_err;
mv.as_int = tmp_mv.as_int;
}
}
// Experimental search in an older reference frame
if (cm->current_video_frame > 1)
{
// Simple 0,0 motion with no mv overhead
zz_motion_search( cpi, x, gld_yv12,
&gf_motion_error, recon_yoffset );
first_pass_motion_search(cpi, x, &zero_ref_mv,
&tmp_mv.as_mv, gld_yv12,
&gf_motion_error, recon_yoffset);
if ( (gf_motion_error < motion_error) &&
(gf_motion_error < this_error))
{
second_ref_count++;
}
// Reset to last frame as reference buffer
xd->pre.y_buffer = lst_yv12->y_buffer + recon_yoffset;
xd->pre.u_buffer = lst_yv12->u_buffer + recon_uvoffset;
xd->pre.v_buffer = lst_yv12->v_buffer + recon_uvoffset;
// In accumulating a score for the older reference frame
// take the best of the motion predicted score and
// the intra coded error (just as will be done for)
// accumulation of "coded_error" for the last frame.
if ( gf_motion_error < this_error )
sr_coded_error += gf_motion_error;
else
sr_coded_error += this_error;
}
else
sr_coded_error += motion_error;
/* Intra assumed best */
best_ref_mv.as_int = 0;
if (motion_error <= this_error)
{
// Keep a count of cases where the inter and intra were
// very close and very low. This helps with scene cut
// detection for example in cropped clips with black bars
// at the sides or top and bottom.
if( (((this_error-intrapenalty) * 9) <=
(motion_error*10)) &&
(this_error < (2*intrapenalty)) )
{
neutral_count++;
}
mv.as_mv.row <<= 3;
mv.as_mv.col <<= 3;
this_error = motion_error;
vp8_set_mbmode_and_mvs(x, NEWMV, &mv);
vp8_encode_inter16x16y(IF_RTCD(&cpi->rtcd), x);
sum_mvr += mv.as_mv.row;
sum_mvr_abs += abs(mv.as_mv.row);
sum_mvc += mv.as_mv.col;
sum_mvc_abs += abs(mv.as_mv.col);
sum_mvrs += mv.as_mv.row * mv.as_mv.row;
sum_mvcs += mv.as_mv.col * mv.as_mv.col;
intercount++;
best_ref_mv.as_int = mv.as_int;
// Was the vector non-zero
if (mv.as_int)
{
mvcount++;
// Was it different from the last non zero vector
if ( mv.as_int != lastmv_as_int )
new_mv_count++;
lastmv_as_int = mv.as_int;
// Does the Row vector point inwards or outwards
if (mb_row < cm->mb_rows / 2)
{
if (mv.as_mv.row > 0)
sum_in_vectors--;
else if (mv.as_mv.row < 0)
sum_in_vectors++;
}
else if (mb_row > cm->mb_rows / 2)
{
if (mv.as_mv.row > 0)
sum_in_vectors++;
else if (mv.as_mv.row < 0)
sum_in_vectors--;
}
// Does the Row vector point inwards or outwards
if (mb_col < cm->mb_cols / 2)
{
if (mv.as_mv.col > 0)
sum_in_vectors--;
else if (mv.as_mv.col < 0)
sum_in_vectors++;
}
else if (mb_col > cm->mb_cols / 2)
{
if (mv.as_mv.col > 0)
sum_in_vectors++;
else if (mv.as_mv.col < 0)
sum_in_vectors--;
}
}
}
}
else
sr_coded_error += (int64_t)this_error;
coded_error += (int64_t)this_error;
// adjust to the next column of macroblocks
x->src.y_buffer += 16;
x->src.u_buffer += 8;
x->src.v_buffer += 8;
recon_yoffset += 16;
recon_uvoffset += 8;
}
// adjust to the next row of mbs
x->src.y_buffer += 16 * x->src.y_stride - 16 * cm->mb_cols;
x->src.u_buffer += 8 * x->src.uv_stride - 8 * cm->mb_cols;
x->src.v_buffer += 8 * x->src.uv_stride - 8 * cm->mb_cols;
//extend the recon for intra prediction
vp8_extend_mb_row(new_yv12, xd->dst.y_buffer + 16, xd->dst.u_buffer + 8, xd->dst.v_buffer + 8);
vp8_clear_system_state(); //__asm emms;
}
vp8_clear_system_state(); //__asm emms;
{
double weight = 0.0;
FIRSTPASS_STATS fps;
fps.frame = cm->current_video_frame ;
fps.intra_error = intra_error >> 8;
fps.coded_error = coded_error >> 8;
fps.sr_coded_error = sr_coded_error >> 8;
weight = simple_weight(cpi->Source);
if (weight < 0.1)
weight = 0.1;
fps.ssim_weighted_pred_err = fps.coded_error * weight;
fps.pcnt_inter = 0.0;
fps.pcnt_motion = 0.0;
fps.MVr = 0.0;
fps.mvr_abs = 0.0;
fps.MVc = 0.0;
fps.mvc_abs = 0.0;
fps.MVrv = 0.0;
fps.MVcv = 0.0;
fps.mv_in_out_count = 0.0;
fps.new_mv_count = 0.0;
fps.count = 1.0;
fps.pcnt_inter = 1.0 * (double)intercount / cm->MBs;
fps.pcnt_second_ref = 1.0 * (double)second_ref_count / cm->MBs;
fps.pcnt_neutral = 1.0 * (double)neutral_count / cm->MBs;
if (mvcount > 0)
{
fps.MVr = (double)sum_mvr / (double)mvcount;
fps.mvr_abs = (double)sum_mvr_abs / (double)mvcount;
fps.MVc = (double)sum_mvc / (double)mvcount;
fps.mvc_abs = (double)sum_mvc_abs / (double)mvcount;
fps.MVrv = ((double)sum_mvrs - (fps.MVr * fps.MVr / (double)mvcount)) / (double)mvcount;
fps.MVcv = ((double)sum_mvcs - (fps.MVc * fps.MVc / (double)mvcount)) / (double)mvcount;
fps.mv_in_out_count = (double)sum_in_vectors / (double)(mvcount * 2);
fps.new_mv_count = new_mv_count;
fps.pcnt_motion = 1.0 * (double)mvcount / cpi->common.MBs;
}
// TODO: handle the case when duration is set to 0, or something less
// than the full time between subsequent cpi->source_time_stamp s .
fps.duration = cpi->source->ts_end
- cpi->source->ts_start;
// don't want to do output stats with a stack variable!
memcpy(cpi->twopass.this_frame_stats,
&fps,
sizeof(FIRSTPASS_STATS));
output_stats(cpi, cpi->output_pkt_list, cpi->twopass.this_frame_stats);
accumulate_stats(cpi->twopass.total_stats, &fps);
}
// Copy the previous Last Frame back into gf and and arf buffers if
// the prediction is good enough... but also dont allow it to lag too far
if ((cpi->twopass.sr_update_lag > 3) ||
((cm->current_video_frame > 0) &&
(cpi->twopass.this_frame_stats->pcnt_inter > 0.20) &&
((cpi->twopass.this_frame_stats->intra_error /
cpi->twopass.this_frame_stats->coded_error) > 2.0)))
{
vp8_yv12_copy_frame_ptr(lst_yv12, gld_yv12);
cpi->twopass.sr_update_lag = 1;
}
else
cpi->twopass.sr_update_lag ++;
// swap frame pointers so last frame refers to the frame we just compressed
vp8_swap_yv12_buffer(lst_yv12, new_yv12);
vp8_yv12_extend_frame_borders(lst_yv12);
// Special case for the first frame. Copy into the GF buffer as a second reference.
if (cm->current_video_frame == 0)
{
vp8_yv12_copy_frame_ptr(lst_yv12, gld_yv12);
}
// use this to see what the first pass reconstruction looks like
if (0)
{
char filename[512];
FILE *recon_file;
sprintf(filename, "enc%04d.yuv", (int) cm->current_video_frame);
if (cm->current_video_frame == 0)
recon_file = fopen(filename, "wb");
else
recon_file = fopen(filename, "ab");
if(fwrite(lst_yv12->buffer_alloc, lst_yv12->frame_size, 1, recon_file));
fclose(recon_file);
}
cm->current_video_frame++;
}
// Estimate a cost per mb attributable to overheads such as the coding of
// modes and motion vectors.
// Currently simplistic in its assumptions for testing.
//
double bitcost( double prob )
{
return -(log( prob ) / log( 2.0 ));
}
static long long estimate_modemvcost(VP8_COMP *cpi,
FIRSTPASS_STATS * fpstats)
{
int mv_cost;
int mode_cost;
double av_pct_inter = fpstats->pcnt_inter / fpstats->count;
double av_pct_motion = fpstats->pcnt_motion / fpstats->count;
double av_intra = (1.0 - av_pct_inter);
double zz_cost;
double motion_cost;
double intra_cost;
zz_cost = bitcost(av_pct_inter - av_pct_motion);
motion_cost = bitcost(av_pct_motion);
intra_cost = bitcost(av_intra);
// Estimate of extra bits per mv overhead for mbs
// << 9 is the normalization to the (bits * 512) used in vp8_bits_per_mb
mv_cost = ((int)(fpstats->new_mv_count / fpstats->count) * 8) << 9;
// Crude estimate of overhead cost from modes
// << 9 is the normalization to (bits * 512) used in vp8_bits_per_mb
mode_cost =
(int)( ( ((av_pct_inter - av_pct_motion) * zz_cost) +
(av_pct_motion * motion_cost) +
(av_intra * intra_cost) ) * cpi->common.MBs ) << 9;
//return mv_cost + mode_cost;
// TODO PGW Fix overhead costs for extended Q range
return 0;
}
static double calc_correction_factor( double err_per_mb,
double err_divisor,
double pt_low,
double pt_high,
int Q )
{
double power_term;
double error_term = err_per_mb / err_divisor;
double correction_factor;
// Adjustment based on actual quantizer to power term.
power_term = (vp8_convert_qindex_to_q(Q) * 0.01) + pt_low;
power_term = (power_term > pt_high) ? pt_high : power_term;
// Adjustments to error term
// TBD
// Calculate correction factor
correction_factor = pow(error_term, power_term);
// Clip range
correction_factor =
(correction_factor < 0.05)
? 0.05 : (correction_factor > 2.0) ? 2.0 : correction_factor;
return correction_factor;
}
// Given a current maxQ value sets a range for future values.
// PGW TODO..
// This code removes direct dependency on QIndex to determin the range
// (now uses the actual quantizer) but has not been tuned.
static void adjust_maxq_qrange(VP8_COMP *cpi)
{
int i;
double q;
// Set the max corresponding to cpi->avg_q * 2.0
q = cpi->avg_q * 2.0;
cpi->twopass.maxq_max_limit = cpi->worst_quality;
for ( i = cpi->best_quality; i <= cpi->worst_quality; i++ )
{
cpi->twopass.maxq_max_limit = i;
if ( vp8_convert_qindex_to_q(i) >= q )
break;
}
// Set the min corresponding to cpi->avg_q * 0.5
q = cpi->avg_q * 0.5;
cpi->twopass.maxq_min_limit = cpi->best_quality;
for ( i = cpi->worst_quality; i >= cpi->best_quality; i-- )
{
cpi->twopass.maxq_min_limit = i;
if ( vp8_convert_qindex_to_q(i) <= q )
break;
}
}
static int estimate_max_q(VP8_COMP *cpi,
FIRSTPASS_STATS * fpstats,
int section_target_bandwitdh,
int overhead_bits )
{
int Q;
int num_mbs = cpi->common.MBs;
int target_norm_bits_per_mb;
double section_err = (fpstats->coded_error / fpstats->count);
double sr_err_diff;
double sr_correction;
double err_per_mb = section_err / num_mbs;
double err_correction_factor;
double speed_correction = 1.0;
int overhead_bits_per_mb;
if (section_target_bandwitdh <= 0)
return cpi->twopass.maxq_max_limit; // Highest value allowed
target_norm_bits_per_mb =
(section_target_bandwitdh < (1 << 20))
? (512 * section_target_bandwitdh) / num_mbs
: 512 * (section_target_bandwitdh / num_mbs);
// Look at the drop in prediction quality between the last frame
// and the GF buffer (which contained an older frame).
sr_err_diff =
(fpstats->sr_coded_error - fpstats->coded_error) /
(fpstats->count * cpi->common.MBs);
sr_correction = (sr_err_diff / 32.0);
sr_correction = pow( sr_correction, 0.25 );
if ( sr_correction < 0.75 )
sr_correction = 0.75;
else if ( sr_correction > 1.25 )
sr_correction = 1.25;
// Calculate a corrective factor based on a rolling ratio of bits spent
// vs target bits
if ((cpi->rolling_target_bits > 0) &&
(cpi->active_worst_quality < cpi->worst_quality))
{
double rolling_ratio;
rolling_ratio = (double)cpi->rolling_actual_bits /
(double)cpi->rolling_target_bits;
if (rolling_ratio < 0.95)
cpi->twopass.est_max_qcorrection_factor -= 0.005;
else if (rolling_ratio > 1.05)
cpi->twopass.est_max_qcorrection_factor += 0.005;
cpi->twopass.est_max_qcorrection_factor =
(cpi->twopass.est_max_qcorrection_factor < 0.1)
? 0.1
: (cpi->twopass.est_max_qcorrection_factor > 10.0)
? 10.0 : cpi->twopass.est_max_qcorrection_factor;
}
// Corrections for higher compression speed settings
// (reduced compression expected)
if (cpi->compressor_speed == 1)
{
if (cpi->oxcf.cpu_used <= 5)
speed_correction = 1.04 + (cpi->oxcf.cpu_used * 0.04);
else
speed_correction = 1.25;
}
// Estimate of overhead bits per mb
// Correction to overhead bits for min allowed Q.
// PGW TODO.. This code is broken for the extended Q range
// for now overhead set to 0.
overhead_bits_per_mb = overhead_bits / num_mbs;
overhead_bits_per_mb *= pow( 0.98, (double)cpi->twopass.maxq_min_limit );
// Try and pick a max Q that will be high enough to encode the
// content at the given rate.
for (Q = cpi->twopass.maxq_min_limit; Q < cpi->twopass.maxq_max_limit; Q++)
{
int bits_per_mb_at_this_q;
err_correction_factor =
calc_correction_factor(err_per_mb, ERR_DIVISOR, 0.4, 0.90, Q) *
sr_correction * speed_correction *
cpi->twopass.est_max_qcorrection_factor;
if ( err_correction_factor < 0.05 )
err_correction_factor = 0.05;
else if ( err_correction_factor > 5.0 )
err_correction_factor = 5.0;
bits_per_mb_at_this_q =
vp8_bits_per_mb(INTER_FRAME, Q) + overhead_bits_per_mb;
bits_per_mb_at_this_q = (int)(.5 + err_correction_factor *
(double)bits_per_mb_at_this_q);
// Mode and motion overhead
// As Q rises in real encode loop rd code will force overhead down
// We make a crude adjustment for this here as *.98 per Q step.
// PGW TODO.. This code is broken for the extended Q range
// for now overhead set to 0.
//overhead_bits_per_mb = (int)((double)overhead_bits_per_mb * 0.98);
if (bits_per_mb_at_this_q <= target_norm_bits_per_mb)
break;
}
// Restriction on active max q for constrained quality mode.
if ( (cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY) &&
(Q < cpi->cq_target_quality) )
{
Q = cpi->cq_target_quality;
}
// Adjust maxq_min_limit and maxq_max_limit limits based on
// averaga q observed in clip for non kf/gf/arf frames
// Give average a chance to settle though.
// PGW TODO.. This code is broken for the extended Q range
if ( (cpi->ni_frames >
((unsigned int)cpi->twopass.total_stats->count >> 8)) &&
(cpi->ni_frames > 150) )
{
adjust_maxq_qrange( cpi );
}
return Q;
}
// For cq mode estimate a cq level that matches the observed
// complexity and data rate.
static int estimate_cq( VP8_COMP *cpi,
FIRSTPASS_STATS * fpstats,
int section_target_bandwitdh,
int overhead_bits )
{
int Q;
int num_mbs = cpi->common.MBs;
int target_norm_bits_per_mb;
double section_err = (fpstats->coded_error / fpstats->count);
double err_per_mb = section_err / num_mbs;
double err_correction_factor;
double sr_err_diff;
double sr_correction;
double speed_correction = 1.0;
double clip_iiratio;
double clip_iifactor;
int overhead_bits_per_mb;
target_norm_bits_per_mb = (section_target_bandwitdh < (1 << 20))
? (512 * section_target_bandwitdh) / num_mbs
: 512 * (section_target_bandwitdh / num_mbs);
// Estimate of overhead bits per mb
overhead_bits_per_mb = overhead_bits / num_mbs;
// Corrections for higher compression speed settings
// (reduced compression expected)
if (cpi->compressor_speed == 1)
{
if (cpi->oxcf.cpu_used <= 5)
speed_correction = 1.04 + (cpi->oxcf.cpu_used * 0.04);
else
speed_correction = 1.25;
}
// Look at the drop in prediction quality between the last frame
// and the GF buffer (which contained an older frame).
sr_err_diff =
(fpstats->sr_coded_error - fpstats->coded_error) /
(fpstats->count * cpi->common.MBs);
sr_correction = (sr_err_diff / 32.0);
sr_correction = pow( sr_correction, 0.25 );
if ( sr_correction < 0.75 )
sr_correction = 0.75;
else if ( sr_correction > 1.25 )
sr_correction = 1.25;
// II ratio correction factor for clip as a whole
clip_iiratio = cpi->twopass.total_stats->intra_error /
DOUBLE_DIVIDE_CHECK(cpi->twopass.total_stats->coded_error);
clip_iifactor = 1.0 - ((clip_iiratio - 10.0) * 0.025);
if (clip_iifactor < 0.80)
clip_iifactor = 0.80;
// Try and pick a Q that can encode the content at the given rate.
for (Q = 0; Q < MAXQ; Q++)
{
int bits_per_mb_at_this_q;
// Error per MB based correction factor
err_correction_factor =
calc_correction_factor(err_per_mb, 100.0, 0.4, 0.90, Q) *
sr_correction * speed_correction * clip_iifactor;
if ( err_correction_factor < 0.05 )
err_correction_factor = 0.05;
else if ( err_correction_factor > 5.0 )
err_correction_factor = 5.0;
bits_per_mb_at_this_q =
vp8_bits_per_mb(INTER_FRAME, Q) + overhead_bits_per_mb;
bits_per_mb_at_this_q = (int)(.5 + err_correction_factor *
(double)bits_per_mb_at_this_q);
// Mode and motion overhead
// As Q rises in real encode loop rd code will force overhead down
// We make a crude adjustment for this here as *.98 per Q step.
// PGW TODO.. This code is broken for the extended Q range
// for now overhead set to 0.
overhead_bits_per_mb = (int)((double)overhead_bits_per_mb * 0.98);
if (bits_per_mb_at_this_q <= target_norm_bits_per_mb)
break;
}
// Clip value to range "best allowed to (worst allowed - 1)"
Q = select_cq_level( Q );
if ( Q >= cpi->worst_quality )
Q = cpi->worst_quality - 1;
if ( Q < cpi->best_quality )
Q = cpi->best_quality;
return Q;
}
extern void vp8_new_frame_rate(VP8_COMP *cpi, double framerate);
void vp8_init_second_pass(VP8_COMP *cpi)
{
FIRSTPASS_STATS this_frame;
FIRSTPASS_STATS *start_pos;
double lower_bounds_min_rate = FRAME_OVERHEAD_BITS*cpi->oxcf.frame_rate;
double two_pass_min_rate = (double)(cpi->oxcf.target_bandwidth
* cpi->oxcf.two_pass_vbrmin_section / 100);
if (two_pass_min_rate < lower_bounds_min_rate)
two_pass_min_rate = lower_bounds_min_rate;
zero_stats(cpi->twopass.total_stats);
zero_stats(cpi->twopass.total_left_stats);
if (!cpi->twopass.stats_in_end)
return;
*cpi->twopass.total_stats = *cpi->twopass.stats_in_end;
*cpi->twopass.total_left_stats = *cpi->twopass.total_stats;
// each frame can have a different duration, as the frame rate in the source
// isn't guaranteed to be constant. The frame rate prior to the first frame
// encoded in the second pass is a guess. However the sum duration is not.
// Its calculated based on the actual durations of all frames from the first
// pass.
vp8_new_frame_rate(cpi, 10000000.0 * cpi->twopass.total_stats->count / cpi->twopass.total_stats->duration);
cpi->output_frame_rate = cpi->oxcf.frame_rate;
cpi->twopass.bits_left = (int64_t)(cpi->twopass.total_stats->duration * cpi->oxcf.target_bandwidth / 10000000.0) ;
cpi->twopass.bits_left -= (int64_t)(cpi->twopass.total_stats->duration * two_pass_min_rate / 10000000.0);
// Calculate a minimum intra value to be used in determining the IIratio
// scores used in the second pass. We have this minimum to make sure
// that clips that are static but "low complexity" in the intra domain
// are still boosted appropriately for KF/GF/ARF
cpi->twopass.kf_intra_err_min = KF_MB_INTRA_MIN * cpi->common.MBs;
cpi->twopass.gf_intra_err_min = GF_MB_INTRA_MIN * cpi->common.MBs;
// This variable monitors how far behind the second ref update is lagging
cpi->twopass.sr_update_lag = 1;
// Scan the first pass file and calculate an average Intra / Inter error score ratio for the sequence
{
double sum_iiratio = 0.0;
double IIRatio;
start_pos = cpi->twopass.stats_in; // Note starting "file" position
while (input_stats(cpi, &this_frame) != EOF)
{
IIRatio = this_frame.intra_error / DOUBLE_DIVIDE_CHECK(this_frame.coded_error);
IIRatio = (IIRatio < 1.0) ? 1.0 : (IIRatio > 20.0) ? 20.0 : IIRatio;
sum_iiratio += IIRatio;
}
cpi->twopass.avg_iiratio = sum_iiratio / DOUBLE_DIVIDE_CHECK((double)cpi->twopass.total_stats->count);
// Reset file position
reset_fpf_position(cpi, start_pos);
}
// Scan the first pass file and calculate a modified total error based upon the bias/power function
// used to allocate bits
{
start_pos = cpi->twopass.stats_in; // Note starting "file" position
cpi->twopass.modified_error_total = 0.0;
cpi->twopass.modified_error_used = 0.0;
while (input_stats(cpi, &this_frame) != EOF)
{
cpi->twopass.modified_error_total += calculate_modified_err(cpi, &this_frame);
}
cpi->twopass.modified_error_left = cpi->twopass.modified_error_total;
reset_fpf_position(cpi, start_pos); // Reset file position
}
}
void vp8_end_second_pass(VP8_COMP *cpi)
{
}
// This function gives and estimate of how badly we believe
// the prediction quality is decaying from frame to frame.
static double get_prediction_decay_rate( VP8_COMP *cpi,
FIRSTPASS_STATS *next_frame)
{
double prediction_decay_rate;
double second_ref_decay;
double mb_sr_err_diff;
// Initial basis is the % mbs inter coded
prediction_decay_rate = next_frame->pcnt_inter;
// Look at the observed drop in prediction quality between the last frame
// and the GF buffer (which contains an older frame).
mb_sr_err_diff =
(next_frame->sr_coded_error - next_frame->coded_error) /
(cpi->common.MBs);
second_ref_decay = 1.0 - (mb_sr_err_diff / 512.0);
second_ref_decay = pow( second_ref_decay, 0.5 );
if ( second_ref_decay < 0.85 )
second_ref_decay = 0.85;
else if ( second_ref_decay > 1.0 )
second_ref_decay = 1.0;
if ( second_ref_decay < prediction_decay_rate )
prediction_decay_rate = second_ref_decay;
return prediction_decay_rate;
}
// Function to test for a condition where a complex transition is followed
// by a static section. For example in slide shows where there is a fade
// between slides. This is to help with more optimal kf and gf positioning.
static int detect_transition_to_still(
VP8_COMP *cpi,
int frame_interval,
int still_interval,
double loop_decay_rate,
double last_decay_rate )
{
BOOL trans_to_still = FALSE;
// Break clause to detect very still sections after motion
// For example a static image after a fade or other transition
// instead of a clean scene cut.
if ( (frame_interval > MIN_GF_INTERVAL) &&
(loop_decay_rate >= 0.999) &&
(last_decay_rate < 0.9) )
{
int j;
FIRSTPASS_STATS * position = cpi->twopass.stats_in;
FIRSTPASS_STATS tmp_next_frame;
double zz_inter;
// Look ahead a few frames to see if static condition
// persists...
for ( j = 0; j < still_interval; j++ )
{
if (EOF == input_stats(cpi, &tmp_next_frame))
break;
zz_inter =
(tmp_next_frame.pcnt_inter - tmp_next_frame.pcnt_motion);
if ( zz_inter < 0.999 )
break;
}
// Reset file position
reset_fpf_position(cpi, position);
// Only if it does do we signal a transition to still
if ( j == still_interval )
trans_to_still = TRUE;
}
return trans_to_still;
}
// This function detects a flash through the high relative pcnt_second_ref
// score in the frame following a flash frame. The offset passed in should
// reflect this
static BOOL detect_flash( VP8_COMP *cpi, int offset )
{
FIRSTPASS_STATS next_frame;
BOOL flash_detected = FALSE;
// Read the frame data.
// The return is FALSE (no flash detected) if not a valid frame
if ( read_frame_stats(cpi, &next_frame, offset) != EOF )
{
// What we are looking for here is a situation where there is a
// brief break in prediction (such as a flash) but subsequent frames
// are reasonably well predicted by an earlier (pre flash) frame.
// The recovery after a flash is indicated by a high pcnt_second_ref
// comapred to pcnt_inter.
if ( (next_frame.pcnt_second_ref > next_frame.pcnt_inter) &&
(next_frame.pcnt_second_ref >= 0.5 ) )
{
flash_detected = TRUE;
}
}
return flash_detected;
}
// Update the motion related elements to the GF arf boost calculation
static void accumulate_frame_motion_stats(
VP8_COMP *cpi,
FIRSTPASS_STATS * this_frame,
double * this_frame_mv_in_out,
double * mv_in_out_accumulator,
double * abs_mv_in_out_accumulator,
double * mv_ratio_accumulator )
{
//double this_frame_mv_in_out;
double this_frame_mvr_ratio;
double this_frame_mvc_ratio;
double motion_pct;
// Accumulate motion stats.
motion_pct = this_frame->pcnt_motion;
// Accumulate Motion In/Out of frame stats
*this_frame_mv_in_out = this_frame->mv_in_out_count * motion_pct;
*mv_in_out_accumulator += this_frame->mv_in_out_count * motion_pct;
*abs_mv_in_out_accumulator +=
fabs(this_frame->mv_in_out_count * motion_pct);
// Accumulate a measure of how uniform (or conversely how random)
// the motion field is. (A ratio of absmv / mv)
if (motion_pct > 0.05)
{
this_frame_mvr_ratio = fabs(this_frame->mvr_abs) /
DOUBLE_DIVIDE_CHECK(fabs(this_frame->MVr));
this_frame_mvc_ratio = fabs(this_frame->mvc_abs) /
DOUBLE_DIVIDE_CHECK(fabs(this_frame->MVc));
*mv_ratio_accumulator +=
(this_frame_mvr_ratio < this_frame->mvr_abs)
? (this_frame_mvr_ratio * motion_pct)
: this_frame->mvr_abs * motion_pct;
*mv_ratio_accumulator +=
(this_frame_mvc_ratio < this_frame->mvc_abs)
? (this_frame_mvc_ratio * motion_pct)
: this_frame->mvc_abs * motion_pct;
}
}
// Calculate a baseline boost number for the current frame.
static double calc_frame_boost(
VP8_COMP *cpi,
FIRSTPASS_STATS * this_frame,
double this_frame_mv_in_out )
{
double frame_boost;
// Underlying boost factor is based on inter intra error ratio
if (this_frame->intra_error > cpi->twopass.gf_intra_err_min)
frame_boost = (IIFACTOR * this_frame->intra_error /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
else
frame_boost = (IIFACTOR * cpi->twopass.gf_intra_err_min /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
// Increase boost for frames where new data coming into frame
// (eg zoom out). Slightly reduce boost if there is a net balance
// of motion out of the frame (zoom in).
// The range for this_frame_mv_in_out is -1.0 to +1.0
if (this_frame_mv_in_out > 0.0)
frame_boost += frame_boost * (this_frame_mv_in_out * 2.0);
// In extreme case boost is halved
else
frame_boost += frame_boost * (this_frame_mv_in_out / 2.0);
// Clip to maximum
if (frame_boost > GF_RMAX)
frame_boost = GF_RMAX;
return frame_boost;
}
static int calc_arf_boost(
VP8_COMP *cpi,
int offset,
int f_frames,
int b_frames,
int *f_boost,
int *b_boost )
{
FIRSTPASS_STATS this_frame;
int i;
double boost_score = 0.0;
double mv_ratio_accumulator = 0.0;
double decay_accumulator = 1.0;
double this_frame_mv_in_out = 0.0;
double mv_in_out_accumulator = 0.0;
double abs_mv_in_out_accumulator = 0.0;
int arf_boost;
BOOL flash_detected = FALSE;
// Search forward from the proposed arf/next gf position
for ( i = 0; i < f_frames; i++ )
{
if ( read_frame_stats(cpi, &this_frame, (i+offset)) == EOF )
break;
// Update the motion related elements to the boost calculation
accumulate_frame_motion_stats( cpi, &this_frame,
&this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator, &mv_ratio_accumulator );
// We want to discount the the flash frame itself and the recovery
// frame that follows as both will have poor scores.
flash_detected = detect_flash(cpi, (i+offset)) ||
detect_flash(cpi, (i+offset+1));
// Cumulative effect of prediction quality decay
if ( !flash_detected )
{
decay_accumulator =
decay_accumulator *
get_prediction_decay_rate(cpi, &this_frame);
decay_accumulator =
decay_accumulator < 0.1 ? 0.1 : decay_accumulator;
}
boost_score += (decay_accumulator *
calc_frame_boost( cpi, &this_frame, this_frame_mv_in_out ));
}
*f_boost = boost_score;
// Reset for backward looking loop
boost_score = 0.0;
mv_ratio_accumulator = 0.0;
decay_accumulator = 1.0;
this_frame_mv_in_out = 0.0;
mv_in_out_accumulator = 0.0;
abs_mv_in_out_accumulator = 0.0;
// Search backward towards last gf position
for ( i = -1; i >= -b_frames; i-- )
{
if ( read_frame_stats(cpi, &this_frame, (i+offset)) == EOF )
break;
// Update the motion related elements to the boost calculation
accumulate_frame_motion_stats( cpi, &this_frame,
&this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator, &mv_ratio_accumulator );
// We want to discount the the flash frame itself and the recovery
// frame that follows as both will have poor scores.
flash_detected = detect_flash(cpi, (i+offset)) ||
detect_flash(cpi, (i+offset+1));
// Cumulative effect of prediction quality decay
if ( !flash_detected )
{
decay_accumulator =
decay_accumulator *
get_prediction_decay_rate(cpi, &this_frame);
decay_accumulator =
decay_accumulator < 0.1 ? 0.1 : decay_accumulator;
}
boost_score += (decay_accumulator *
calc_frame_boost( cpi, &this_frame, this_frame_mv_in_out ));
}
*b_boost = boost_score;
arf_boost = (*f_boost + *b_boost);
if ( arf_boost < ((b_frames + f_frames) * 20) )
arf_boost = ((b_frames + f_frames) * 20);
return arf_boost;
}
static void configure_arnr_filter( VP8_COMP *cpi, FIRSTPASS_STATS *this_frame )
{
int half_gf_int;
int frames_after_arf;
int frames_bwd = cpi->oxcf.arnr_max_frames - 1;
int frames_fwd = cpi->oxcf.arnr_max_frames - 1;
// Define the arnr filter width for this group of frames:
// We only filter frames that lie within a distance of half
// the GF interval from the ARF frame. We also have to trap
// cases where the filter extends beyond the end of clip.
// Note: this_frame->frame has been updated in the loop
// so it now points at the ARF frame.
half_gf_int = cpi->baseline_gf_interval >> 1;
frames_after_arf = cpi->twopass.total_stats->count -
this_frame->frame - 1;
switch (cpi->oxcf.arnr_type)
{
case 1: // Backward filter
frames_fwd = 0;
if (frames_bwd > half_gf_int)
frames_bwd = half_gf_int;
break;
case 2: // Forward filter
if (frames_fwd > half_gf_int)
frames_fwd = half_gf_int;
if (frames_fwd > frames_after_arf)
frames_fwd = frames_after_arf;
frames_bwd = 0;
break;
case 3: // Centered filter
default:
frames_fwd >>= 1;
if (frames_fwd > frames_after_arf)
frames_fwd = frames_after_arf;
if (frames_fwd > half_gf_int)
frames_fwd = half_gf_int;
frames_bwd = frames_fwd;
// For even length filter there is one more frame backward
// than forward: e.g. len=6 ==> bbbAff, len=7 ==> bbbAfff.
if (frames_bwd < half_gf_int)
frames_bwd += (cpi->oxcf.arnr_max_frames+1) & 0x1;
break;
}
cpi->active_arnr_frames = frames_bwd + 1 + frames_fwd;
}
// Analyse and define a gf/arf group .
static void define_gf_group(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame)
{
FIRSTPASS_STATS next_frame;
FIRSTPASS_STATS *start_pos;
int i;
double boost_score = 0.0;
double old_boost_score = 0.0;
double gf_group_err = 0.0;
double gf_first_frame_err = 0.0;
double mod_frame_err = 0.0;
double mv_ratio_accumulator = 0.0;
double decay_accumulator = 1.0;
double zero_motion_accumulator = 1.0;
double loop_decay_rate = 1.00; // Starting decay rate
double last_loop_decay_rate = 1.00;
double this_frame_mv_in_out = 0.0;
double mv_in_out_accumulator = 0.0;
double abs_mv_in_out_accumulator = 0.0;
int max_bits = frame_max_bits(cpi); // Max for a single frame
unsigned int allow_alt_ref =
cpi->oxcf.play_alternate && cpi->oxcf.lag_in_frames;
int f_boost = 0;
int b_boost = 0;
BOOL flash_detected;
cpi->twopass.gf_group_bits = 0;
vp8_clear_system_state(); //__asm emms;
start_pos = cpi->twopass.stats_in;
vpx_memset(&next_frame, 0, sizeof(next_frame)); // assure clean
// Load stats for the current frame.
mod_frame_err = calculate_modified_err(cpi, this_frame);
// Note the error of the frame at the start of the group (this will be
// the GF frame error if we code a normal gf
gf_first_frame_err = mod_frame_err;
// Special treatment if the current frame is a key frame (which is also
// a gf). If it is then its error score (and hence bit allocation) need
// to be subtracted out from the calculation for the GF group
if (cpi->common.frame_type == KEY_FRAME)
gf_group_err -= gf_first_frame_err;
// Scan forward to try and work out how many frames the next gf group
// should contain and what level of boost is appropriate for the GF
// or ARF that will be coded with the group
i = 0;
while (((i < cpi->twopass.static_scene_max_gf_interval) ||
((cpi->twopass.frames_to_key - i) < MIN_GF_INTERVAL)) &&
(i < cpi->twopass.frames_to_key))
{
i++; // Increment the loop counter
// Accumulate error score of frames in this gf group
mod_frame_err = calculate_modified_err(cpi, this_frame);
gf_group_err += mod_frame_err;
if (EOF == input_stats(cpi, &next_frame))
break;
// Test for the case where there is a brief flash but the prediction
// quality back to an earlier frame is then restored.
flash_detected = detect_flash(cpi, 0);
// Update the motion related elements to the boost calculation
accumulate_frame_motion_stats( cpi, &next_frame,
&this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator, &mv_ratio_accumulator );
// Cumulative effect of prediction quality decay
if ( !flash_detected )
{
last_loop_decay_rate = loop_decay_rate;
loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
decay_accumulator = decay_accumulator * loop_decay_rate;
// Monitor for static sections.
if ( (next_frame.pcnt_inter - next_frame.pcnt_motion) <
zero_motion_accumulator )
{
zero_motion_accumulator =
(next_frame.pcnt_inter - next_frame.pcnt_motion);
}
// Break clause to detect very still sections after motion
// (for example a staic image after a fade or other transition).
if ( detect_transition_to_still( cpi, i, 5, loop_decay_rate,
last_loop_decay_rate ) )
{
allow_alt_ref = FALSE;
break;
}
}
// Calculate a boost number for this frame
boost_score +=
( decay_accumulator *
calc_frame_boost( cpi, &next_frame, this_frame_mv_in_out ) );
// Break out conditions.
if (
// Break at cpi->max_gf_interval unless almost totally static
(i >= cpi->max_gf_interval && (zero_motion_accumulator < 0.995)) ||
(
// Dont break out with a very short interval
(i > MIN_GF_INTERVAL) &&
// Dont break out very close to a key frame
((cpi->twopass.frames_to_key - i) >= MIN_GF_INTERVAL) &&
((boost_score > 125.0) || (next_frame.pcnt_inter < 0.75)) &&
(!flash_detected) &&
((mv_ratio_accumulator > 100.0) ||
(abs_mv_in_out_accumulator > 3.0) ||
(mv_in_out_accumulator < -2.0) ||
((boost_score - old_boost_score) < 12.5))
) )
{
boost_score = old_boost_score;
break;
}
vpx_memcpy(this_frame, &next_frame, sizeof(*this_frame));
old_boost_score = boost_score;
}
// Dont allow a gf too near the next kf
if ((cpi->twopass.frames_to_key - i) < MIN_GF_INTERVAL)
{
while (i < cpi->twopass.frames_to_key)
{
i++;
if (EOF == input_stats(cpi, this_frame))
break;
if (i < cpi->twopass.frames_to_key)
{
mod_frame_err = calculate_modified_err(cpi, this_frame);
gf_group_err += mod_frame_err;
}
}
}
// Set the interval till the next gf or arf.
cpi->baseline_gf_interval = i;
// Should we use the alternate refernce frame
if (allow_alt_ref &&
(i < cpi->oxcf.lag_in_frames ) &&
(i >= MIN_GF_INTERVAL) &&
// dont use ARF very near next kf
(i <= (cpi->twopass.frames_to_key - MIN_GF_INTERVAL)) &&
((next_frame.pcnt_inter > 0.75) ||
(next_frame.pcnt_second_ref > 0.5)) &&
((mv_in_out_accumulator / (double)i > -0.2) ||
(mv_in_out_accumulator > -2.0)) &&
(boost_score > 100))
{
// Alterrnative boost calculation for alt ref
cpi->gfu_boost = calc_arf_boost( cpi, 0, (i-1), (i-1), &f_boost, &b_boost );
cpi->source_alt_ref_pending = TRUE;
configure_arnr_filter( cpi, this_frame );
}
else
{
cpi->gfu_boost = (int)boost_score;
cpi->source_alt_ref_pending = FALSE;
}
// Now decide how many bits should be allocated to the GF group as a
// proportion of those remaining in the kf group.
// The final key frame group in the clip is treated as a special case
// where cpi->twopass.kf_group_bits is tied to cpi->twopass.bits_left.
// This is also important for short clips where there may only be one
// key frame.
if (cpi->twopass.frames_to_key >= (int)(cpi->twopass.total_stats->count -
cpi->common.current_video_frame))
{
cpi->twopass.kf_group_bits =
(cpi->twopass.bits_left > 0) ? cpi->twopass.bits_left : 0;
}
// Calculate the bits to be allocated to the group as a whole
if ((cpi->twopass.kf_group_bits > 0) &&
(cpi->twopass.kf_group_error_left > 0))
{
cpi->twopass.gf_group_bits =
(int)((double)cpi->twopass.kf_group_bits *
(gf_group_err / (double)cpi->twopass.kf_group_error_left));
}
else
cpi->twopass.gf_group_bits = 0;
cpi->twopass.gf_group_bits =
(cpi->twopass.gf_group_bits < 0)
? 0
: (cpi->twopass.gf_group_bits > cpi->twopass.kf_group_bits)
? cpi->twopass.kf_group_bits : cpi->twopass.gf_group_bits;
// Clip cpi->twopass.gf_group_bits based on user supplied data rate
// variability limit (cpi->oxcf.two_pass_vbrmax_section)
if (cpi->twopass.gf_group_bits > max_bits * cpi->baseline_gf_interval)
cpi->twopass.gf_group_bits = max_bits * cpi->baseline_gf_interval;
// Reset the file position
reset_fpf_position(cpi, start_pos);
// Update the record of error used so far (only done once per gf group)
cpi->twopass.modified_error_used += gf_group_err;
// Assign bits to the arf or gf.
for (i = 0; i <= (cpi->source_alt_ref_pending && cpi->common.frame_type != KEY_FRAME); i++)
{
int boost;
int allocation_chunks;
int Q = (cpi->oxcf.fixed_q < 0) ? cpi->last_q[INTER_FRAME] : cpi->oxcf.fixed_q;
int gf_bits;
boost = (cpi->gfu_boost * vp8_gfboost_qadjust(Q)) / 100;
// Set max and minimum boost and hence minimum allocation
if (boost > ((cpi->baseline_gf_interval + 1) * 200))
boost = ((cpi->baseline_gf_interval + 1) * 200);
else if (boost < 125)
boost = 125;
if ( cpi->source_alt_ref_pending && i == 0 )
allocation_chunks =
((cpi->baseline_gf_interval + 1) * 100) + boost;
else
allocation_chunks =
(cpi->baseline_gf_interval * 100) + (boost - 100);
// Prevent overflow
if ( boost > 1028 )
{
int divisor = boost >> 10;
boost/= divisor;
allocation_chunks /= divisor;
}
// Calculate the number of bits to be spent on the gf or arf based on
// the boost number
gf_bits = (int)((double)boost *
(cpi->twopass.gf_group_bits /
(double)allocation_chunks));
// If the frame that is to be boosted is simpler than the average for
// the gf/arf group then use an alternative calculation
// based on the error score of the frame itself
if (mod_frame_err < gf_group_err / (double)cpi->baseline_gf_interval)
{
double alt_gf_grp_bits;
int alt_gf_bits;
alt_gf_grp_bits =
(double)cpi->twopass.kf_group_bits *
(mod_frame_err * (double)cpi->baseline_gf_interval) /
DOUBLE_DIVIDE_CHECK((double)cpi->twopass.kf_group_error_left);
alt_gf_bits = (int)((double)boost * (alt_gf_grp_bits /
(double)allocation_chunks));
if (gf_bits > alt_gf_bits)
{
gf_bits = alt_gf_bits;
}
}
// Else if it is harder than other frames in the group make sure it at
// least receives an allocation in keeping with its relative error
// score, otherwise it may be worse off than an "un-boosted" frame
else
{
int alt_gf_bits =
(int)((double)cpi->twopass.kf_group_bits *
mod_frame_err /
DOUBLE_DIVIDE_CHECK((double)cpi->twopass.kf_group_error_left));
if (alt_gf_bits > gf_bits)
{
gf_bits = alt_gf_bits;
}
}
// Dont allow a negative value for gf_bits
if (gf_bits < 0)
gf_bits = 0;
gf_bits += cpi->min_frame_bandwidth; // Add in minimum for a frame
if (i == 0)
{
cpi->twopass.gf_bits = gf_bits;
}
if (i == 1 || (!cpi->source_alt_ref_pending && (cpi->common.frame_type != KEY_FRAME)))
{
cpi->per_frame_bandwidth = gf_bits; // Per frame bit target for this frame
}
}
{
// Adjust KF group bits and error remainin
cpi->twopass.kf_group_error_left -= gf_group_err;
cpi->twopass.kf_group_bits -= cpi->twopass.gf_group_bits;
if (cpi->twopass.kf_group_bits < 0)
cpi->twopass.kf_group_bits = 0;
// Note the error score left in the remaining frames of the group.
// For normal GFs we want to remove the error score for the first frame
// of the group (except in Key frame case where this has already
// happened)
if (!cpi->source_alt_ref_pending && cpi->common.frame_type != KEY_FRAME)
cpi->twopass.gf_group_error_left = gf_group_err - gf_first_frame_err;
else
cpi->twopass.gf_group_error_left = gf_group_err;
cpi->twopass.gf_group_bits -= cpi->twopass.gf_bits - cpi->min_frame_bandwidth;
if (cpi->twopass.gf_group_bits < 0)
cpi->twopass.gf_group_bits = 0;
// This condition could fail if there are two kfs very close together
// despite (MIN_GF_INTERVAL) and would cause a devide by 0 in the
// calculation of cpi->twopass.alt_extra_bits.
if ( cpi->baseline_gf_interval >= 3 )
{
int boost = (cpi->source_alt_ref_pending)
? b_boost : cpi->gfu_boost;
if ( boost >= 150 )
{
int pct_extra;
pct_extra = (boost - 100) / 50;
pct_extra = (pct_extra > 20) ? 20 : pct_extra;
cpi->twopass.alt_extra_bits =
(cpi->twopass.gf_group_bits * pct_extra) / 100;
cpi->twopass.gf_group_bits -= cpi->twopass.alt_extra_bits;
cpi->twopass.alt_extra_bits /=
((cpi->baseline_gf_interval-1)>>1);
}
else
cpi->twopass.alt_extra_bits = 0;
}
else
cpi->twopass.alt_extra_bits = 0;
}
if (cpi->common.frame_type != KEY_FRAME)
{
FIRSTPASS_STATS sectionstats;
zero_stats(§ionstats);
reset_fpf_position(cpi, start_pos);
for (i = 0 ; i < cpi->baseline_gf_interval ; i++)
{
input_stats(cpi, &next_frame);
accumulate_stats(§ionstats, &next_frame);
}
avg_stats(§ionstats);
cpi->twopass.section_intra_rating =
sectionstats.intra_error /
DOUBLE_DIVIDE_CHECK(sectionstats.coded_error);
reset_fpf_position(cpi, start_pos);
}
}
// Allocate bits to a normal frame that is neither a gf an arf or a key frame.
static void assign_std_frame_bits(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame)
{
int target_frame_size; // gf_group_error_left
double modified_err;
double err_fraction; // What portion of the remaining GF group error is used by this frame
int max_bits = frame_max_bits(cpi); // Max for a single frame
// Calculate modified prediction error used in bit allocation
modified_err = calculate_modified_err(cpi, this_frame);
if (cpi->twopass.gf_group_error_left > 0)
err_fraction = modified_err / cpi->twopass.gf_group_error_left; // What portion of the remaining GF group error is used by this frame
else
err_fraction = 0.0;
target_frame_size = (int)((double)cpi->twopass.gf_group_bits * err_fraction); // How many of those bits available for allocation should we give it?
// Clip to target size to 0 - max_bits (or cpi->twopass.gf_group_bits) at the top end.
if (target_frame_size < 0)
target_frame_size = 0;
else
{
if (target_frame_size > max_bits)
target_frame_size = max_bits;
if (target_frame_size > cpi->twopass.gf_group_bits)
target_frame_size = cpi->twopass.gf_group_bits;
}
cpi->twopass.gf_group_error_left -= modified_err; // Adjust error remaining
cpi->twopass.gf_group_bits -= target_frame_size; // Adjust bits remaining
if (cpi->twopass.gf_group_bits < 0)
cpi->twopass.gf_group_bits = 0;
target_frame_size += cpi->min_frame_bandwidth; // Add in the minimum number of bits that is set aside for every frame.
cpi->per_frame_bandwidth = target_frame_size; // Per frame bit target for this frame
}
// Make a damped adjustment to the active max q.
int adjust_active_maxq( int old_maxqi, int new_maxqi )
{
int i;
int ret_val = new_maxqi;
double old_q;
double new_q;
double target_q;
old_q = vp8_convert_qindex_to_q( old_maxqi );
new_q = vp8_convert_qindex_to_q( new_maxqi );
target_q = ((old_q * 7.0) + new_q) / 8.0;
if ( target_q > old_q )
{
for ( i = old_maxqi; i <= new_maxqi; i++ )
{
if ( vp8_convert_qindex_to_q( i ) >= target_q )
{
ret_val = i;
break;
}
}
}
else
{
for ( i = old_maxqi; i >= new_maxqi; i-- )
{
if ( vp8_convert_qindex_to_q( i ) <= target_q )
{
ret_val = i;
break;
}
}
}
return ret_val;
}
void vp8_second_pass(VP8_COMP *cpi)
{
int tmp_q;
int frames_left = (int)(cpi->twopass.total_stats->count - cpi->common.current_video_frame);
FIRSTPASS_STATS this_frame;
FIRSTPASS_STATS this_frame_copy;
double this_frame_error;
double this_frame_intra_error;
double this_frame_coded_error;
FIRSTPASS_STATS *start_pos;
int overhead_bits;
if (!cpi->twopass.stats_in)
{
return ;
}
vp8_clear_system_state();
if (EOF == input_stats(cpi, &this_frame))
return;
this_frame_error = this_frame.ssim_weighted_pred_err;
this_frame_intra_error = this_frame.intra_error;
this_frame_coded_error = this_frame.coded_error;
start_pos = cpi->twopass.stats_in;
// keyframe and section processing !
if (cpi->twopass.frames_to_key == 0)
{
// Define next KF group and assign bits to it
vpx_memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
find_next_key_frame(cpi, &this_frame_copy);
}
// Is this a GF / ARF (Note that a KF is always also a GF)
if (cpi->frames_till_gf_update_due == 0)
{
// Define next gf group and assign bits to it
vpx_memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
define_gf_group(cpi, &this_frame_copy);
// If we are going to code an altref frame at the end of the group and the current frame is not a key frame....
// If the previous group used an arf this frame has already benefited from that arf boost and it should not be given extra bits
// If the previous group was NOT coded using arf we may want to apply some boost to this GF as well
if (cpi->source_alt_ref_pending && (cpi->common.frame_type != KEY_FRAME))
{
// Assign a standard frames worth of bits from those allocated to the GF group
int bak = cpi->per_frame_bandwidth;
vpx_memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
assign_std_frame_bits(cpi, &this_frame_copy);
cpi->per_frame_bandwidth = bak;
}
}
// Otherwise this is an ordinary frame
else
{
// Assign bits from those allocated to the GF group
vpx_memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
assign_std_frame_bits(cpi, &this_frame_copy);
}
// Keep a globally available copy of this and the next frame's iiratio.
cpi->twopass.this_iiratio = this_frame_intra_error /
DOUBLE_DIVIDE_CHECK(this_frame_coded_error);
{
FIRSTPASS_STATS next_frame;
if ( lookup_next_frame_stats(cpi, &next_frame) != EOF )
{
cpi->twopass.next_iiratio = next_frame.intra_error /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error);
}
}
// Set nominal per second bandwidth for this frame
cpi->target_bandwidth = cpi->per_frame_bandwidth * cpi->output_frame_rate;
if (cpi->target_bandwidth < 0)
cpi->target_bandwidth = 0;
// Account for mv, mode and other overheads.
overhead_bits = estimate_modemvcost(
cpi, cpi->twopass.total_left_stats );
// Special case code for first frame.
if (cpi->common.current_video_frame == 0)
{
cpi->twopass.est_max_qcorrection_factor = 1.0;
// Set a cq_level in constrained quality mode.
if ( cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY )
{
int est_cq;
est_cq =
estimate_cq( cpi,
cpi->twopass.total_left_stats,
(int)(cpi->twopass.bits_left / frames_left),
overhead_bits );
cpi->cq_target_quality = cpi->oxcf.cq_level;
if ( est_cq > cpi->cq_target_quality )
cpi->cq_target_quality = est_cq;
}
// guess at maxq needed in 2nd pass
cpi->twopass.maxq_max_limit = cpi->worst_quality;
cpi->twopass.maxq_min_limit = cpi->best_quality;
tmp_q = estimate_max_q(
cpi,
cpi->twopass.total_left_stats,
(int)(cpi->twopass.bits_left / frames_left),
overhead_bits );
cpi->active_worst_quality = tmp_q;
cpi->ni_av_qi = tmp_q;
cpi->avg_q = vp8_convert_qindex_to_q( tmp_q );
// Limit the maxq value returned subsequently.
// This increases the risk of overspend or underspend if the initial
// estimate for the clip is bad, but helps prevent excessive
// variation in Q, especially near the end of a clip
// where for example a small overspend may cause Q to crash
adjust_maxq_qrange(cpi);
}
// The last few frames of a clip almost always have to few or too many
// bits and for the sake of over exact rate control we dont want to make
// radical adjustments to the allowed quantizer range just to use up a
// few surplus bits or get beneath the target rate.
else if ( (cpi->common.current_video_frame <
(((unsigned int)cpi->twopass.total_stats->count * 255)>>8)) &&
((cpi->common.current_video_frame + cpi->baseline_gf_interval) <
(unsigned int)cpi->twopass.total_stats->count) )
{
if (frames_left < 1)
frames_left = 1;
tmp_q = estimate_max_q(
cpi,
cpi->twopass.total_left_stats,
(int)(cpi->twopass.bits_left / frames_left),
overhead_bits );
// Make a damped adjustment to active max Q
cpi->active_worst_quality =
adjust_active_maxq( cpi->active_worst_quality, tmp_q );
}
cpi->twopass.frames_to_key --;
// Update the total stats remaining sturcture
subtract_stats(cpi->twopass.total_left_stats, &this_frame );
}
static BOOL test_candidate_kf(VP8_COMP *cpi, FIRSTPASS_STATS *last_frame, FIRSTPASS_STATS *this_frame, FIRSTPASS_STATS *next_frame)
{
BOOL is_viable_kf = FALSE;
// Does the frame satisfy the primary criteria of a key frame
// If so, then examine how well it predicts subsequent frames
if ((this_frame->pcnt_second_ref < 0.10) &&
(next_frame->pcnt_second_ref < 0.10) &&
((this_frame->pcnt_inter < 0.05) ||
(
((this_frame->pcnt_inter - this_frame->pcnt_neutral) < .35) &&
((this_frame->intra_error / DOUBLE_DIVIDE_CHECK(this_frame->coded_error)) < 2.5) &&
((fabs(last_frame->coded_error - this_frame->coded_error) / DOUBLE_DIVIDE_CHECK(this_frame->coded_error) > .40) ||
(fabs(last_frame->intra_error - this_frame->intra_error) / DOUBLE_DIVIDE_CHECK(this_frame->intra_error) > .40) ||
((next_frame->intra_error / DOUBLE_DIVIDE_CHECK(next_frame->coded_error)) > 3.5)
)
)
)
)
{
int i;
FIRSTPASS_STATS *start_pos;
FIRSTPASS_STATS local_next_frame;
double boost_score = 0.0;
double old_boost_score = 0.0;
double decay_accumulator = 1.0;
double next_iiratio;
vpx_memcpy(&local_next_frame, next_frame, sizeof(*next_frame));
// Note the starting file position so we can reset to it
start_pos = cpi->twopass.stats_in;
// Examine how well the key frame predicts subsequent frames
for (i = 0 ; i < 16; i++)
{
next_iiratio = (IIKFACTOR1 * local_next_frame.intra_error / DOUBLE_DIVIDE_CHECK(local_next_frame.coded_error)) ;
if (next_iiratio > RMAX)
next_iiratio = RMAX;
// Cumulative effect of decay in prediction quality
if (local_next_frame.pcnt_inter > 0.85)
decay_accumulator = decay_accumulator * local_next_frame.pcnt_inter;
else
decay_accumulator = decay_accumulator * ((0.85 + local_next_frame.pcnt_inter) / 2.0);
//decay_accumulator = decay_accumulator * local_next_frame.pcnt_inter;
// Keep a running total
boost_score += (decay_accumulator * next_iiratio);
// Test various breakout clauses
if ((local_next_frame.pcnt_inter < 0.05) ||
(next_iiratio < 1.5) ||
(((local_next_frame.pcnt_inter -
local_next_frame.pcnt_neutral) < 0.20) &&
(next_iiratio < 3.0)) ||
((boost_score - old_boost_score) < 3.0) ||
(local_next_frame.intra_error < 200)
)
{
break;
}
old_boost_score = boost_score;
// Get the next frame details
if (EOF == input_stats(cpi, &local_next_frame))
break;
}
// If there is tolerable prediction for at least the next 3 frames then break out else discard this pottential key frame and move on
if (boost_score > 30.0 && (i > 3))
is_viable_kf = TRUE;
else
{
// Reset the file position
reset_fpf_position(cpi, start_pos);
is_viable_kf = FALSE;
}
}
return is_viable_kf;
}
static void find_next_key_frame(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame)
{
int i,j;
FIRSTPASS_STATS last_frame;
FIRSTPASS_STATS first_frame;
FIRSTPASS_STATS next_frame;
FIRSTPASS_STATS *start_position;
double decay_accumulator = 1.0;
double zero_motion_accumulator = 1.0;
double boost_score = 0;
double old_boost_score = 0.0;
double loop_decay_rate;
double kf_mod_err = 0.0;
double kf_group_err = 0.0;
double kf_group_intra_err = 0.0;
double kf_group_coded_err = 0.0;
double recent_loop_decay[8] = {1.0,1.0,1.0,1.0,1.0,1.0,1.0,1.0};
vpx_memset(&next_frame, 0, sizeof(next_frame)); // assure clean
vp8_clear_system_state(); //__asm emms;
start_position = cpi->twopass.stats_in;
cpi->common.frame_type = KEY_FRAME;
// is this a forced key frame by interval
cpi->this_key_frame_forced = cpi->next_key_frame_forced;
// Clear the alt ref active flag as this can never be active on a key frame
cpi->source_alt_ref_active = FALSE;
// Kf is always a gf so clear frames till next gf counter
cpi->frames_till_gf_update_due = 0;
cpi->twopass.frames_to_key = 1;
// Take a copy of the initial frame details
vpx_memcpy(&first_frame, this_frame, sizeof(*this_frame));
cpi->twopass.kf_group_bits = 0; // Total bits avaialable to kf group
cpi->twopass.kf_group_error_left = 0; // Group modified error score.
kf_mod_err = calculate_modified_err(cpi, this_frame);
// find the next keyframe
i = 0;
while (cpi->twopass.stats_in < cpi->twopass.stats_in_end)
{
// Accumulate kf group error
kf_group_err += calculate_modified_err(cpi, this_frame);
// These figures keep intra and coded error counts for all frames including key frames in the group.
// The effect of the key frame itself can be subtracted out using the first_frame data collected above
kf_group_intra_err += this_frame->intra_error;
kf_group_coded_err += this_frame->coded_error;
// load a the next frame's stats
vpx_memcpy(&last_frame, this_frame, sizeof(*this_frame));
input_stats(cpi, this_frame);
// Provided that we are not at the end of the file...
if (cpi->oxcf.auto_key
&& lookup_next_frame_stats(cpi, &next_frame) != EOF)
{
// Normal scene cut check
if ( test_candidate_kf(cpi, &last_frame, this_frame, &next_frame) )
{
break;
}
// How fast is prediction quality decaying
loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
// We want to know something about the recent past... rather than
// as used elsewhere where we are concened with decay in prediction
// quality since the last GF or KF.
recent_loop_decay[i%8] = loop_decay_rate;
decay_accumulator = 1.0;
for (j = 0; j < 8; j++)
{
decay_accumulator = decay_accumulator * recent_loop_decay[j];
}
// Special check for transition or high motion followed by a
// to a static scene.
if ( detect_transition_to_still( cpi, i,
(cpi->key_frame_frequency-i),
loop_decay_rate,
decay_accumulator ) )
{
break;
}
// Step on to the next frame
cpi->twopass.frames_to_key ++;
// If we don't have a real key frame within the next two
// forcekeyframeevery intervals then break out of the loop.
if (cpi->twopass.frames_to_key >= 2 *(int)cpi->key_frame_frequency)
break;
} else
cpi->twopass.frames_to_key ++;
i++;
}
// If there is a max kf interval set by the user we must obey it.
// We already breakout of the loop above at 2x max.
// This code centers the extra kf if the actual natural
// interval is between 1x and 2x
if (cpi->oxcf.auto_key
&& cpi->twopass.frames_to_key > (int)cpi->key_frame_frequency )
{
FIRSTPASS_STATS *current_pos = cpi->twopass.stats_in;
FIRSTPASS_STATS tmp_frame;
cpi->twopass.frames_to_key /= 2;
// Copy first frame details
vpx_memcpy(&tmp_frame, &first_frame, sizeof(first_frame));
// Reset to the start of the group
reset_fpf_position(cpi, start_position);
kf_group_err = 0;
kf_group_intra_err = 0;
kf_group_coded_err = 0;
// Rescan to get the correct error data for the forced kf group
for( i = 0; i < cpi->twopass.frames_to_key; i++ )
{
// Accumulate kf group errors
kf_group_err += calculate_modified_err(cpi, &tmp_frame);
kf_group_intra_err += tmp_frame.intra_error;
kf_group_coded_err += tmp_frame.coded_error;
// Load a the next frame's stats
input_stats(cpi, &tmp_frame);
}
// Reset to the start of the group
reset_fpf_position(cpi, current_pos);
cpi->next_key_frame_forced = TRUE;
}
else
cpi->next_key_frame_forced = FALSE;
// Special case for the last frame of the file
if (cpi->twopass.stats_in >= cpi->twopass.stats_in_end)
{
// Accumulate kf group error
kf_group_err += calculate_modified_err(cpi, this_frame);
// These figures keep intra and coded error counts for all frames including key frames in the group.
// The effect of the key frame itself can be subtracted out using the first_frame data collected above
kf_group_intra_err += this_frame->intra_error;
kf_group_coded_err += this_frame->coded_error;
}
// Calculate the number of bits that should be assigned to the kf group.
if ((cpi->twopass.bits_left > 0) && (cpi->twopass.modified_error_left > 0.0))
{
// Max for a single normal frame (not key frame)
int max_bits = frame_max_bits(cpi);
// Maximum bits for the kf group
int64_t max_grp_bits;
// Default allocation based on bits left and relative
// complexity of the section
cpi->twopass.kf_group_bits = (int64_t)( cpi->twopass.bits_left *
( kf_group_err /
cpi->twopass.modified_error_left ));
// Clip based on maximum per frame rate defined by the user.
max_grp_bits = (int64_t)max_bits * (int64_t)cpi->twopass.frames_to_key;
if (cpi->twopass.kf_group_bits > max_grp_bits)
cpi->twopass.kf_group_bits = max_grp_bits;
}
else
cpi->twopass.kf_group_bits = 0;
// Reset the first pass file position
reset_fpf_position(cpi, start_position);
// determine how big to make this keyframe based on how well the subsequent frames use inter blocks
decay_accumulator = 1.0;
boost_score = 0.0;
loop_decay_rate = 1.00; // Starting decay rate
for (i = 0 ; i < cpi->twopass.frames_to_key ; i++)
{
double r;
if (EOF == input_stats(cpi, &next_frame))
break;
if (next_frame.intra_error > cpi->twopass.kf_intra_err_min)
r = (IIKFACTOR2 * next_frame.intra_error /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
else
r = (IIKFACTOR2 * cpi->twopass.kf_intra_err_min /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
if (r > RMAX)
r = RMAX;
// Monitor for static sections.
if ( (next_frame.pcnt_inter - next_frame.pcnt_motion) <
zero_motion_accumulator )
{
zero_motion_accumulator =
(next_frame.pcnt_inter - next_frame.pcnt_motion);
}
// How fast is prediction quality decaying
if ( !detect_flash(cpi, 0) )
{
loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
decay_accumulator = decay_accumulator * loop_decay_rate;
decay_accumulator = decay_accumulator < 0.1 ? 0.1 : decay_accumulator;
}
boost_score += (decay_accumulator * r);
if ((i > MIN_GF_INTERVAL) &&
((boost_score - old_boost_score) < 6.25))
{
break;
}
old_boost_score = boost_score;
}
{
FIRSTPASS_STATS sectionstats;
zero_stats(§ionstats);
reset_fpf_position(cpi, start_position);
for (i = 0 ; i < cpi->twopass.frames_to_key ; i++)
{
input_stats(cpi, &next_frame);
accumulate_stats(§ionstats, &next_frame);
}
avg_stats(§ionstats);
cpi->twopass.section_intra_rating =
sectionstats.intra_error
/ DOUBLE_DIVIDE_CHECK(sectionstats.coded_error);
}
// Reset the first pass file position
reset_fpf_position(cpi, start_position);
// Work out how many bits to allocate for the key frame itself
if (1)
{
int kf_boost = boost_score;
int allocation_chunks;
int alt_kf_bits;
if ( kf_boost < 300 )
{
kf_boost += (cpi->twopass.frames_to_key * 3);
if ( kf_boost > 300 )
kf_boost = 300;
}
if (kf_boost < 250) // Min KF boost
kf_boost = 250;
// Make a note of baseline boost and the zero motion
// accumulator value for use elsewhere.
cpi->kf_boost = kf_boost;
cpi->kf_zeromotion_pct = (int)(zero_motion_accumulator * 100.0);
// We do three calculations for kf size.
// The first is based on the error score for the whole kf group.
// The second (optionaly) on the key frames own error if this is
// smaller than the average for the group.
// The final one insures that the frame receives at least the
// allocation it would have received based on its own error score vs
// the error score remaining
// Special case if the sequence appears almost totaly static
// In this case we want to spend almost all of the bits on the
// key frame.
// cpi->twopass.frames_to_key-1 because key frame itself is taken
// care of by kf_boost.
if ( zero_motion_accumulator >= 0.99 )
{
allocation_chunks =
((cpi->twopass.frames_to_key - 1) * 10) + kf_boost;
}
else
{
allocation_chunks =
((cpi->twopass.frames_to_key - 1) * 100) + kf_boost;
}
// Prevent overflow
if ( kf_boost > 1028 )
{
int divisor = kf_boost >> 10;
kf_boost /= divisor;
allocation_chunks /= divisor;
}
cpi->twopass.kf_group_bits = (cpi->twopass.kf_group_bits < 0) ? 0 : cpi->twopass.kf_group_bits;
// Calculate the number of bits to be spent on the key frame
cpi->twopass.kf_bits = (int)((double)kf_boost * ((double)cpi->twopass.kf_group_bits / (double)allocation_chunks));
// If the key frame is actually easier than the average for the
// kf group (which does sometimes happen... eg a blank intro frame)
// Then use an alternate calculation based on the kf error score
// which should give a smaller key frame.
if (kf_mod_err < kf_group_err / cpi->twopass.frames_to_key)
{
double alt_kf_grp_bits =
((double)cpi->twopass.bits_left *
(kf_mod_err * (double)cpi->twopass.frames_to_key) /
DOUBLE_DIVIDE_CHECK(cpi->twopass.modified_error_left));
alt_kf_bits = (int)((double)kf_boost *
(alt_kf_grp_bits / (double)allocation_chunks));
if (cpi->twopass.kf_bits > alt_kf_bits)
{
cpi->twopass.kf_bits = alt_kf_bits;
}
}
// Else if it is much harder than other frames in the group make sure
// it at least receives an allocation in keeping with its relative
// error score
else
{
alt_kf_bits =
(int)((double)cpi->twopass.bits_left *
(kf_mod_err /
DOUBLE_DIVIDE_CHECK(cpi->twopass.modified_error_left)));
if (alt_kf_bits > cpi->twopass.kf_bits)
{
cpi->twopass.kf_bits = alt_kf_bits;
}
}
cpi->twopass.kf_group_bits -= cpi->twopass.kf_bits;
cpi->twopass.kf_bits += cpi->min_frame_bandwidth; // Add in the minimum frame allowance
cpi->per_frame_bandwidth = cpi->twopass.kf_bits; // Peer frame bit target for this frame
cpi->target_bandwidth = cpi->twopass.kf_bits * cpi->output_frame_rate; // Convert to a per second bitrate
}
// Note the total error score of the kf group minus the key frame itself
cpi->twopass.kf_group_error_left = (int)(kf_group_err - kf_mod_err);
// Adjust the count of total modified error left.
// The count of bits left is adjusted elsewhere based on real coded frame sizes
cpi->twopass.modified_error_left -= kf_group_err;
}